Video and lesson investigations on the topic of movies. Key concepts include:
- Moving pictures are made from numerous still pictures.
- If the different pictures are viewed one after another, at a certain speed, the brain can be ‘fooled’ into thinking that there is only one moving picture.
- Films look jerky if they are projected slowly.
- For the cinema screen, modern film is filmed and projected at 24 frames per second.
- Early silent films were made and projected at only about 18 frames per second. This is why they sometimes seemed to be ‘jerky’.
- Human eyes can register only up to twelve separate images per second. If more images per second reach the eye, they tend to ‘join up’ and are perceived as ‘moving’ in a continuous way.
- This effect is known as the ‘persistence of vision’ and is what makes ‘movie’ action seem realistic.